Supplemental data

Files in this Data Supplement:

• supplemental material - Supplementary Figure 1.� Summary of FRET and electrophysiological studies. The closed channel displays an inter fluorophore distance of ~26��.� When ATP binds the channels open to an initial selective state (I1), but there is no detectable cytosolic conformational change.� In the continued presence of ATP P2X2 channels undergo permeability changes and open to I2 with a conformational rearrangement of the cytosolic domain.� Following removal of ATP the pore closes before the cytosolic domain relaxes to the resting state in ~200�s.� We term this the permissive state for I2 because the pore is closed but the cytosolic domain is still in a permissive conformation, and propose that from here the channels may enter either the closed or I2 state.� We cannot rule out the possibility that the permissive state may represent a component of the I2 desensitised state.� The permissive state may explain why entry to the I2 state displays history-dependence as determined by electrophysiological studies (Fig 4).
• supplemental material - Supplemental Table